Heat-treating apparatus



Dec. 25, 1928.

L. E. HOWARD HEAT TREATING APPARATUS 2 Sheets-Sheet 1 Filed Nov. 16, 1926 waved p607 I Leslie 0 a d 5 aql alz w Patented Dec. 25, 1928.

UNITED STATES PATENT OFFICE.

LESLIE E. HOWARD, OF LOGKIORT, NEW YORK, ASSIGNOB TO SIMONDS SAW AND STEEL COMPANY, OF FITCHBURG, MASSACHUSETTS, A CORPORATION OF MAS- SACHUSETTS.

: HEAT-TREATING APPARATUS.

Application filed November 16, 1926. Serial No. 148,689. 7

This invention relates to an improved method and means for continuously conveying articles through heat treating apparatus, and more particularly through an annealing furnace designed for the bright annealing of metal objects in a gaseous atmosphere which excludes oxygen or common air and thus prevents oxidization of the sur face metal.

The invention discloses apparatus for conveying metal articles through a furnace of this character which not only permits any desired rate of movement of the articles being heat treated, but also allowsthe loading of conveyor units to take place at a controllable rate. These conveyor units are adapted to carry different types of metal objects, such as reels of wire, small metal parts or the like, yet they are interchangeable and are readily moved to various parts of the plant before or after the heat treating operation. The units are constructed to permit free circulation of air about the metal bein treated and to be rotated in order to afford uniform heat treatment for all parts of the metal.

Furthermore, conveying means of this character is readily repaired, may still be operative when certain parts break, its units may be quickly removed and replaced, and therefore it permits of practically continuous operation of the plant with little or no need of shut-clowns in order to repair the conveying mechanism, load or unload, etc. Furthermore, conveying means of this character is designed to be manufactured at a low first cost and is adaptable to installation in a wide variety of heat treating systems of this general character.

The above and further advantages and objects of the invention will be apparent to those skilled in the art upon a reading of the subjoined description and claims in conjunction with the accompanying drawings, in which: 7

Fig. l is a to plan view of an annealing furnace using t e improved conveying system;

Fig. 2 is a side elevation of the same furnace with a part of the wall thereof broken away; i

Fig. i a section on line of Fig. 4

Fig. 4 is an elevational view of a con veyor unit;

Fig. 5 is an end view of a part of the same unit; v

Fig. dis a central sectional view of another form of unit;

Fig. 7 is a section on line 77 of Fig. 1;

Fig. 8 is a plan view of a portion of the conveyor train; and Fig. 9 is a section on line 99 of Fig. 2.

Conveyor means of the type illustrated herein is designed to be used in a wide variety of furnaces, ovens and the like wherein metal objects, such as reels of wire or small metal parts are to be annealed or treated in any analogous manner. The conveyor system is more particularly illustrated as used in conjunction with an annealing furnace adapted to accomplish bright annealing of metal in an inertgas, such as nitrogen, hydrogen, or preferably ordinary illuminating gas.

preferably comprises a sealing vat of oil or other suitable liquid. A suitable gas which is lighter than air, such for example as ordinary illuminating gas is trapped in the passage and is prevented by the liquid seal from passing out of the passage with objects moving therethrough, thus excluding air and preventing oxidization of the metal surfaces. The elevated heating zone preferably is covered with suitable heat-resistant material and is provided with suitable heating elements, such as the electric resistance units 5, which are adapted to raise the temperature of the interior of this portion of the passageway onfurnace- Fig. 9 slows A furnace of this character, shown Figs. 1, 2 and 9, may comprise a passagewayv :plate 36 is detachablexand such an arrangement in cross section, the resistance elements 5 being located in the side walls and above the passageway and be ing surrounded with layers of tire brick or similar heat-resistant material.

Any suitable supporting means, such as the framework 6, is provided to support'the elevated heating chamber of thefurnace in the manner shown. The outlet Tofpassageway 1 preferably is at one side of the inlet, as indicated in Fig. 1.,t0 permit the ready removal of objects therefrom. As thus clescribed the annealing furnace is illustrative of a common type of furnate which '11] ay be varied in many suitable ways to suitdifferent installations and plants and is mere- 1y exemplary of what is well known .in the art.

The present invention pertains more particularly to the provision of improved conveyor means for supporting and carrying articles which pass through a heat treating furnace of this general character. l-Ieretofore ithas been commonzin theart'to provide continuous chains, moving tables, and the like to support objects to be annealed. How.-

ever, many disadvantages which have accompanied the use of such conveying means are obviated by the present mechanism which comprises aseries of conveyor units or rolls .20 and having peripheral portions '21 which are .adapted to roll :in a suitable :flanged .or grooved :trackr22, or upon the floor of the passageway. These peripheral portions-of :the conveyor unit or roll may be the rims of spider zplatesBG at either end of rolls20, while the intermediate part thereof comprises .a'suitable core 28 of spider-dike cross sect-ionghaving radiating ribs 27=aligned with theradiating arms of the spider plates and a central opening 25 to receive and rotate about an axle 26. If desired, :the core .23 and one of thespider plates 36 may be formed integrally or permanently united as disclosed in Fig. 4. Preferably at least one is provided with depressions 73*to interfit with :the end of the eore:23 lilig. 5) being held to the same by studs 30 which are provided with suitable taper pins 31 passing through transverse openings 32 (Fig. 7).

The axle 26 of the roll projects from either end thereof and is provided with detachable screw-threaded heads 38 and bearing portions 39 ofwrestricted diameter ad joining the threaded heads, which are adapted to engage openings in connecting links 40 to tie the conveyor rollers together in a series or train. Links 40, .as disclosed more specifically in Fig. '8, may comprise metal bars havingopenmgs ateither end and being slightly *bent, whereby one end thereof is adapted to engage the outer portion of the bearing 39 upon one axle and the opposite end is adapted to engage the inner portion portion :of passage sections 3 of the bearing upon the corresponding end of the axle of the adjoining roll.

Beneath the inlet end of the passageway 1 is located a suitable lifting mechanisrn of any form, preferably a hydraulic jack 49 provided with a manually adjustable control valve and having a reciprocating plunger '50 in alignment with the opening of the passageway .to push conveyors into the same.

The conveyor units, being assembeld in a a distance approximately equal .to the center to center dimension of one of the links 40, and that the train will be maintained in its advanced position not only by the friction throughout the system but the pawls 45.

Preferably a pair of depending links 40 are secured :to the last roll which is thus beingheld in its advanced position and an additional roll is brought into a suitable position above the retracted plunger 50 and is joined :to the train attachmentof its a-Xle vto the depending .links d0, while another pair of links are secured 'upon this .roll for connection to the succeeding roll. The ,'acl

4:9 is then actuated to dorce the added roll upward to an advanced position in passageway 1 wherein it is engaged by pawls 41-5., and thus the entire'train or series of rolls is advanced as each new roll is added. .Meantime conveyor units issuing from the outlet of the passage may be detached from the series at any desirable intervals,

Track 22 ,may be located upon the lower and 2,'while 1n the reversably curved portion 4, tracks 22 may be located ateither sideof the conveyor train, the track in the .upper section termiating at El and .the track .in the lower section beginning at 62, Fig. 2, thus the rolls may continue their rolling movement on a grooved track, although their direction of rotation will be reversed at :this portion of their path.

The construction of the conveyor rolls wlth the spiderhke core and connecting openings in the end plates permits the ready circulation of air about the central portion of the roll as well .as about its periphery. Therefore, assuming that wlre or similar material to be annealed is placed upon the roll eitherby removing end plate 36 or in any suitable way, hot air will have a maxilll i mum opportunity to circulate about the wire and to effect uniform annealing thereof as the .roll rotates on its journey through. the heating zone of the furnace, exposing different portions of the wire in succession to the region of higher temperature. It is often advantageous to provide suitable spacer plates 35 to separate the reels upon one roll. If desired, these spacer plates maybe either fiat or may be corrugated as shown or otherwise shaped in order to aid the circulation of air about the wire and between the reels thereof. Plates 35 may be frictionally or otherwise held upon the core and may be removed when spider 36 is detached.

WVhen it is desired to anneal various small objects such, for example, as small metal fittings, conveyor rolls, adapted to be containers, as illustrated in Fig. 6, may be used interchangeably in each conveyor train 01' series with the conveyor rolls previously described. Such a unit comprises a cylindrical container having an axle 26 and having numerous openings or perforations 72 in its outer wall and also in its ends, if desired. The unit has a removable end 71 secured thereto by pins 61 in a manner similar to the arrangement of pins 30 in the preferred form of the invention, these pins preferably projecting from one end of the cylindrical wall and permitting the removal of one end 71 of the cylindrical container so that metal objects can be placed-loosely therein. Circulation of hot air through conveyor unit 70 is permitted by the perforations, and the slow rotation thereof will result in the relative movement and turning of the various objects carried in the unit so that uniform exposure of the various metal surfaces to the heat will result.

It is particularly advantageous to have conveyor means of this character in which the units may be interchangeably assembled. either to convey reels of wire or the like or various small objects or in which, if desired, many of the units in the train may be passed through the furnace without carrying metal parts when the plant or furnace is not working at full capacity. In case one of the links 40 should break the other link and the juxtaposed position of successive rolls will ordinarily permit the continued operation of the train until the broken link appears at the outlet of the furnace and may be replaced. The manually controlled hydraulic 'ack permits the rapidity of movement 0 the conveyor train to be altered at will and the loading of the same to take place during any desired interval of time. The track 22 which extends through the furnace passageway may have suitable continuations so that the conveyor units may be rolled to any convenient part of the plant.

I claim:

1. The combination of heat-treating apparatus having an upwardly inclined en trance passage and conveyor mechanism to transport articles through the apparatus, said mechanism comprisinga series of rolls, a jack adjoining the entrance passage, said jack having a plunger adapted to push the rolls into the same, and means to hold the rolls in advanced position when so pushed to permit retraction of the plunger and addition of another roll to the series.

2. The combination of heat-treating apparatus having an upwardly inclined entrance passage and conveyor mechanism to transport articles through the apparatus, said mechanism comprising a series of rolls,

a hydraulic jack adjoining the entrance passage, said jack having a plunger to push the rolls into the same, manual control means for the jack means to hold the rolls in advanced position when so pushed, to permit retraction of the plunger and addition of another roll to the series, whereby the speed of conveyor movement and of adding new rolls to the series may be controllably varied.

3. The .combination of heat-treating apparatus having an upwardly inclined entrance passage and conveyor mechanism to transport articles through the apparatus, said mechanism comprising a series of rolls, a jack adjoining the entrance passage, said jack having a plunger to push the rolls into the same, and automatic means to hold the rolls in advanced position when so pushed in order to permit retraction of the plunger and addition of another roll to the series.

4. A conveyor of the class described comprising a series of rolls, links connecting the rolls in line and permitting their inclependent rotation, a cooperating track adapted to engage the peripheries of the rolls, one end of each roll being removable to permit the ready placing of articles thereon.

5. A conveyor system of the class described, comprising a series of rolls, means for adding rolls to and removing rolls from the series, a controllable pusher for pushing the series of rolls, and a spring controlled pawl for holding the rolls in ad vanced position while a new roll is being added.

6. A conveying system of the class de scribed comprising a series of rolls, means for adding rolls to and removing rolls from the series, a controllable pusher for pushing the rolls, said pusher comprising a reciprocable plunger, and latch means to hold the rolls in advanced position whereby the plunger may be retracted and a new roll added to the series.

7. A conveyor system of the class described comprising a series of rolls, links connectin the axes of the rolls and permitting tlieir independent rotation, peripheral portions of the rolls being adapted to engage a track said rolls being readily detachable from the links it and thus "from the series and beingiinterchangeable in relation to the links and series, certain of said rolls comprising containers adaptedv to receive articles therein and other of said rolls comprising reels to receive Wound material thereon, whereby. the series of conveyor units may comprise interchangeable containers or reels.

8. A conveyor system of the class described comprising a series of rolls, links connecting the axes ottherolls and pen mitting their indefinite rotation, periph eral portions of the rolls being adapted to engage a track, said rolls being readily detachable from the links and thus from the series and beinginterchangeable in relation to the links and series, certain of. said rolls comprising containers adapted to receive articles therein and, having openings to permit circulation or air. about said artieles, other of said rolls comprising reels adapted to receive Wound material upon a ribbed core provided with passages between the ribs, whereby the series of conveyor units may comprise any desired proportion ofreels and of containers,'both of which permit air circulation about the material carried thereby.

LESLIE HOWARD. 

